Summary of Work: Personality types are construed as constellations of features that uniquely define discrete groups of individuals. The 10 personality disorders of the DSM-IV (American Psychiatric Association, 2000) are perhaps one of the better-known typologies. Types are conceptually convenient because they summarize many traits in a single label, but until recently most researchers agreed that there was little evidence for the existence of discrete personality types. Several groups of researchers have advanced a personality typology based upon three replicable, empirical person clusters derived from measures of the Five-Factor Model. These clusters or types have been labeled Resilient (below average Neuroticism (N) scores and above average Extraversion (E), Openness (O), Agreeableness (A) and Conscientiousness (C) scores), Overcontrolled (high in N, low in E and O), and Undercontrolled (below average in A and C). The present research attempted to replicate these types in four large and diverse adult samples: (1) the Baltimore Longitudinal Study of Aging (N=1,856), (2) the East Baltimore Epidemiologic Catchment Area study (N=486), (3) the UNC Alumni Heart Study (N=2,420), and (4) a HIV risk reduction intervention study (N=274). Ward?s hierarchical cluster procedure followed by k-means centering was used to derive empirical clusters from the 5 NEO-PI-R domain scores in each sample. To assess the replicability of empirical clusters to the 3 typological clusters, kappa coefficients were computed. Based upon the kappas, a clear replication of the proposed types was found in only one sample, the ECA (kappa = .62), but several others had a greater-than-chance resemblance. Because these personality types are thought to relate to different patterns of psychopathology, e.g., externalizing problems for the Undercontrolled types, and internalizing problems for the Overcontrolled types, then type membership should be a powerful predictor of certain outcomes. Results in the ECA sample showed that the 3 types predicted measures of psychosocial functioning, depression, and personality disorders. Specifically, Resilient types were less depressed, had superior psychosocial functioning, and fewer personality disorder symptoms. The failure of the 3 personality types to replicate in 3 of the 4 samples leads to the conclusion that they are not robust empirical entities. It should be noted that the Resilient type was empirically replicated in all 4 samples, while the Undercontrolled was replicated in none. Nevertheless, while the types do not refer to distinct homogeneous classes of persons, they do have utility as convenient labels summarizing the combinations of traits that individually and together relate to important outcomes.